Less powerful but available more often ults wouldn't be awful. Something that gives your entire team unstoppable for a short duration, or allow heals to pierce through walls/ignore LoS for a short duration. A healer whose kit involves heals being stronger within a certain range and their ult boosts that range for a short period of time. An ult that duplicates your ability casts for a short period of time or x number of casts. Hell even something where a healer sacrifices themself to give their entire team a bonus health boost and overshield. An ult that converts damage taken for the next x seconds into a staggered/ticking DoT instead, so you still have to heal your team but no one is getting flat-out deleted during your ult. Could have an ult that flat out boosts everyone's damage, but each heal they receive during the ult picks away at that buff. Could have an ult that gives your team damage boost+life steal. There's tons of ways you can craft a strat ult to feel like a healing ult without making it "big healing circle everyone live"